I plan on running in NASA TTD with Nitto NT-01 235/40/17 based on my projected set up. I don't really autocross so I can't recommend the proper tire pressures for that. However, on track, from prior experience, I usually run between 38-40 PSI hot; if I need more rotation, I will back off a little up front and/or increase pressure behind. My wheels will likely be either 17x9 or 18x9, squared set up. I'm not sure on off set.

I just ordered my rims and tires today so I'll be able to contribute to my own thread soon.

For reference, I ordered TR Motorsports MT1 18x8 with Hankook RS3's in a 235/40/18. I just dropped 13lbs/per front tire and 15lbs/per rear tire! That's 56lbs in rotational mass! Should be pretty awesome.

I'm going to run a square set up with Apex 18X8.5 wheels and Hankook RS3 tires. I noticed a lot of cars using these tires at the two track events I've done so far. I haven't received the wheels yet so I'll give a review at a later date. No doubt they will be leaps and bounds better than the stock run-flats that came on my car!

I plan on running in NASA TTD with Nitto NT-01 235/40/17 based on my projected set up. I don't really autocross so I can't recommend the proper tire pressures for that. However, on track, from prior experience, I usually run between 38-40 PSI hot; if I need more rotation, I will back off a little up front and/or increase pressure behind. My wheels will likely be either 17x9 or 18x9, squared set up. I'm not sure on off set.

Has the F30 been classed in TTD already? I run the NT01s in TTC on my E36 M3. I love that tire.

I also have an F30 that I will be putting APEX EC-7s on. You can run a 245 if points allow it and TC Kline says a 255 square on the F30 is very doable.

I work at APEX and we will be doing some fitment testing on the F30 to see what the maximum width fitment is, with and without modifications.

The F30 328i starts in TTD. I ran the Nitto NT-01s on my prior e36 M3 as well, but in TTD. I'd be currious to hear what you guys come up with as the widest set up for the F30. I suppose it depends on whether you have camber plates and/or run spacers. Also, certain coilovers may give you more room inside.

I ran Moda MD15 in 18x8 with Hankook Z214 C51 compound r-comp's in 245/40-18. The tires were leftover from my Evo X. Two are corded due to the lack of negative camber in front so I need to decide what to do next.

I will probably run nt01 next as I can drive to/from the track on that tire. With the Hankooks you really don't want to drive them on the street!!!

I really wish Vorhshlag and/or Ground Control would come out with camber plates soon for the F30. Otherwise, we are left with street tires or r compounds that cord easily. I think I will create another post on here about camber plates and, with the help of others, come up with a list of people interested in them to coax these manufacturers.

A heavily staggered setup like this, 8.5"/245mm and 10"/275mm, is not good for a BMW on the track. You would do much better with 8.5" front and rear. Just because you can fit a wide tire doesn't mean you should.

The reason for the same sizes - square setup - is that BMWs are a little heavier in the front (nothing like an AUDI) so they need every bit as much rubber up there as they have in the back. BTW, a square setup is the best handling mod you can do and should be the first one.

The next handling mod should camber. Here's an excerpt from the above linked article:

Benefits of Negative Camber[/size]
Additional negative camber balances a BMWs handling and significantly increases its performance. Racers typically run an additional -1 degree of camber on the front compared to the rear, sometimes more. From the factory, BMWs typically have +2 degrees more camber in the front compared to the rear. Although this is done to give you early warning in the front tires when you’re going a little too fast in corners it biases grip to the rear tires. By adding negative camber to the front you can more perfectly balance a BMW’s handling by creating similar levels of grip, front and rear.

Wider front tires also contribute to perfectly balanced handling on a BMW. If you want to run aggressively wide tires in the front, negative camber (commonly referred to as “more camber”) is almost always necessary to help clear the front fender by tucking the wheel under it.

JMK007 and I have both taken our F30s to the track and we both drove them hard. He has a review of his and I think I posted my thoughts also. I won't be competing with mine but JMK007 will. He and I have talked on the phone and I can see he knows what he's talking about and I would pay attention to what he has to say.

Thanks for the very helpful response!
So I'm thinking I'll take the advice of the track guys and stick to a square setup. As much as I like the looks of the wide tires and deep concave wheels in the back, handling is more important to me than looks.

I'll read through the fitment link you posted; I trust that info on how much camber is needed to make 9" wheels and wide tires fit up front is in there.

In terms of camber for f30s, I haven't seen too many options yet... I guess lowering will add a few tenths of a degree, and I've read that there are oem replacement knuckles that add 30min (-0.5deg). Would that be enough to fit a 9" wheel and a 255mm tire (or at least a 245) without any rubbing?

Front 245's fit no problem, both on stock suspension and lowered on H&R sports

I autocross the car regularly and there is no evidence of any rubbing on the tires or the fenders

255's are probably doable on the front, but it's going to be close. A little camber adjustment (when that's available, or the OE swivel bearings) or maybe just the right offset would make it no problem

I find the 245 re-11a's to have good grip and square to give the car nice balance. The H&R sport springs also made a significant improvement to the handling and feel of the car, as did a proper alignment

I also hear great things about the new BFG Rivals, great grip, very progressive and phenomenal wear - I will likely try those next

Front 245's fit no problem, both on stock suspension and lowered on H&R sports

I autocross the car regularly and there is no evidence of any rubbing on the tires or the fenders

255's are probably doable on the front, but it's going to be close. A little camber adjustment (when that's available, or the OE swivel bearings) or maybe just the right offset would make it no problem ...

Upon reading this thread we saw a few comments regarding tire sizes in regards to rubbing and would like to chime in with information regarding the F30 wheel and tire fitments.

The OEM F30 Sportline wheel is 18x8" ET34, and the EC-7's are 18x9.0" ET42. The EC-7's extends an additional 5mm on the fender side, while it takes up an additional 21mm of clearance on the strut side in comparison to the Sportline wheels. Also, since the EC-7's are an inch wider, this means that they are approximately 12.5mm wider per side of the wheel (half an inch wider per side of the wheel) than the OEM Sportline wheels. What this means is that using the same tire on the two different wheels will have different results, as the sidewall characteristics of the same tires will be different between the different width wheels. This may be the reason why some have not experienced rubbing issues with the 245/40/18 tire size.

Using the 245/40/18 tire on the 18x8" ET34 wheel is oversized, and due to the tires being ballooned with a narrower wheel, the tires effectively become ~240/40/18 since the tread is pulled in as the tire bead is pulled in. This happens when a tire is mounted on a wheel that is too narrow. Additionally, there would be less sidewall support from a wheel that is too narrow creating sloppier sidewalls, which in turn causes steering response to be less nimble and makes it more difficult to drive a tire at its limits. For street use this may not be an issue, but if one is looking for performance we do recommend the proper tire size and wheel width combination.

I literally went to a bmw cca autox event for the first time ever in my life in my no line 328i with crappy runflat 17" all seasons and i got 2nd place in the turbo stock class which included n54/55 engines (335i, 135i). You dont need any upgrades, you just take your car there and drive the snot out of it. When you no longer have grip because of your skill set, you get wheels and tires.